Chemical treating block for a toilet tank



FIG. 1 is a perspective view of a chemical treating block for a toilet tank showing my new design;

FIG. 2 is a plan view thereof, the side opposite being a mirror image of the side shown; and,

FIG. 3 is an elevational view seen from the top of FIG. 2. 

The ornamental design for a chemical treating block for a toilet tank, as shown and described. 